Quality of life is a new concept in the health area and controversies exist about its application to clinical practice. Studies carried out in Brazil in the nephrology area have indicated the need for further investigations. OBJECTIVE: To analyze the quality of life of patients with different times of hemodialysis. METHODS: The study consisted of application of the questionnare SF-36, collection of demographic, socioeconomic and biochemical data, as well as of the clinical characteristics. RESULTS: The study was conducted on 184 patients, 63% of them males, aged 46±15 years (X±SD), with a hemodialysis time of 30±36 months; 48% had up to 4 years of schooling and 53% belonged to the economic-social classes D and E. Impairment of the different dimensions analyzed was observed, with the poorest results being obtained for Physical Aspects and Vitality. A negative correlation was detected between Age and Functional Capacity, Physical Aspects, Pain, and Vitality, and between Hemodialysis Time and Emotional Aspects. A positive correlation was observed between Schooling and Emotional Aspects and between Hemoglobin and Vitality. We observed that diabetic patients were older than non-diabetic patients and presented lower values for the Functional Capacity and General Health condition dimensions. CONCLUSION: SF-36 proved to be a good instrument for the assessment of the quality of life of hemodialysis patients. The presence of a chronic disease, the need for continuous treatment over a long period of time, advanced age, and the presence of co-morbidities were factors that might interfere with the quality of life of this population.